Field of the Invention
The present invention relates to a method for manufacturing a fiber optic connector assembly and a fiber optic connector assembly manufactured by the method.
Description of the Related Art
The insertion loss of a fiber optic connector is mainly depended on surface polishing quality of an optical fiber to be connected and offset of a fiber core of the optical fiber. The present invention is focused on reducing the offset of the fiber core. During assembling a fiber optic connector, the offset of the fiber core is mainly determined by following three factors: (1) an eccentricity e1′ between a bore of a fiber optic ferrule and an outer circumferential surface of the fiber optic ferrule (see FIG. 1A); (2) an eccentricity e2′ between the fiber core and the coat layer of the optical fiber (see FIG. 1B); (3) a difference Δd between a diameter of the optical fiber and a diameter of the bore of the fiber optic ferrule (see FIG. 1C). In the above three factors, the eccentricity e2′ between the fiber core and the coat layer of the optical fiber has a least effect on the insertion loss of the fiber optic connector.
In prior art, a fiber optic connector assembly having a low insertion loss is generally manufactured by a high precision fiber optical ferrule and by manually adjusting the offset of the fiber core of the optical fiber. In the case of adopting the high precision fiber optical ferrule, please refer to FIGS. 1A, 1B and 1C, it is necessary to reduce the eccentricity e1′ between the bore of the fiber optic ferrule and the outer circumferential surface of the fiber optic ferrule (see FIG. 1A) and the difference Δd between the diameter of the optical fiber and the diameter of the bore of the fiber optic ferrule (see FIG. 1C), so as to reduce the offset of the fiber core of the optical fiber with respect to the outer circumferential surface of the fiber optic ferrule. In this case, however, it greatly increases the cost of the fiber optic connector, and it becomes very difficult to insert the optical fiber into the bore of the fiber optic ferrule. In the case of adopting a manufacturing process of adjusting the offset of the fiber core of the optical fiber, please refer to FIG. 2, the offset between the fiber cores of the optical fibers to be connected during coupling fiber optic connectors can be reduced by adjusting the centers of the fiber cores of the optical fibers into a specific angle zone (indicated by a black sector region in FIG. 2) corresponding to a key 03 (the key 03 is used as a mark for identifying the adjusting region of the optical fiber), for example, as shown in FIG. 2, adjusting the center of the fiber core of the optical fiber from a position 01 outside the black sector region into a position 02 within the black sector region. However, in this case, the fiber optic connectors must be adjusted before coupling. If the fiber optic connectors are not adjusted in advance, the offset between the fiber cores of the optical fibers is random and cannot be controlled. Furthermore, if the fiber optic connector is manufactured by a fiber optic ferrule with higher precision, it also increases the cost of the fiber optic connector and the difficulty to insert the optical fiber into the bore of the fiber optic ferrule.
In another Chinese patent application No. CN201310555118.6 filed by the inventor of the present invention, there is provided a method for manufacturing a fiber optic ferrule, wherein a center of a fiber core of an optical fiber is actively adjusted to accurately align to a center of a fiber optic ferrule. In this way, during matching a pair of fiber optic connectors, the offset between the centers of the fiber cores of the optical fibers connected by the pair of fiber optic connectors is reduced, greatly decreasing the insertion loss of the fiber optic connectors. Thereby, the whole disclosure of said patent application is incorporated herein by reference.
In the present application, the inventor uses the above pre-adjusted fiber optic ferrule with an optical fiber to further manufacture a mechanically coupled fiber optic connector assembly with a low insertion loss.
In the prior art, during manufacturing a fiber optic connector assembly in which a fiber fixed in a ferrule is optically coupled with a fiber of a cable, generally, the fiber fixed in the ferrule and the fiber of the cable are directly inserted into an alignment tool mounted in a housing of a fiber optic connector. However, the offset between the center of the fiber core of the fiber in the ferrule and the center of the fiber core of the fiber of the cable is random and cannot be controlled, that is, the offset between the centers of the fiber cores is randomly distributed in a range of a minimal offset MA1 to a maximal offset MA2, as shown in FIG. 2, the minimal offset MA1 is equal to a difference between an eccentricity of the fiber core of the fiber in the ferrule and an eccentricity of the fiber core of the fiber of the cable, and the maximal offset MA2 is equal to a sum of an eccentricity of the fiber core of the fiber in the ferrule and an eccentricity of the fiber core of the fiber of the cable. Thereby, the performance of the fiber optic connector assembly made by the method in the prior art is not stable and cannot always satisfy predetermined requirements. In order to satisfy predetermined requirements, in the prior art, it generally adopts a high precision cable and a high precision ferrule to manufacture the fiber optic connector assembly. However, as discussed above, it greatly increases the cost of the fiber optic connector assembly.